My fuel gauge is frustrating me, all thought I understand the gauges in these cares sucked from the beginning, but mine is ridiculous.

If I fill up, it will go a little fast full and stay there for a couple days. Then after that the next time I start it up, it says I have maybe half a tank. That's based on memory, but you get the idea.

Just today it said empty, so I put in about $16 in the tank (only like 4 gallons) and it said half a tank. If it was really empty, then that CANNOT be half a tank. I highly doubt we have 8 gallon tanks. That was maybe 2 or 3 hours ago. I just went back out about a half hour ago and it read a 1/4 tank. WHY!

Any ideas on what I can do to fix it? I don't want to rely on my trip odometer, as I reset it often for other reasons, and I just wouldn't remember to go by it.

 

Sounds like the contact in the fuel sender gauge has corrosion and is probably casuing the innacurate readings. You gotta drop the tank to fix that though. You can either get a new sending unit, or pry the cover off the contact for yours and clean it out. Theres a tiny metal box next to the float arm, its held on with 2 metal tabs. You unbend those tabs CAREFULLY and seperate the 2 peices of metal to expose the contact. Clean it off when some laquer or mineral spirts and a soft brush and close it back up.

 

Well, when I bought the car, they already had the "hatch" cut in the floor. Can I just do it that way?

 

Ugh. I hate seeing that hack job. Yea you can pull the fuel sender out that way, but I HIGHLY recommend you do something about that...

 

Since I'll have the carpet pulled back and everything, I'll see if I can find some way to clean it up.

 

The only proper way fix it would be drop the tank and have the sheet metal welded.

 

Still having problems with the gauge. When ever the gauge says the tank is empty, I go to the gas station as I should. If I don't decide to fill it I just put in a few gallons,or like $20. After I starter it up again it says half a tank. I don't understand that! I would understand if the float had gone past the halfway mark during filling and the gauge is reading that, but I doubt that is what happens. I took the whole unit out at one point and moved the float up and down and watched the gauge. it was pretty accurate. All the way up it said full, and all the way down it said empty. In the middle somewhere it seemed pretty accurate too, but I can't for the life of me figure this out!

 

I just got used to reading my Odometer instead of the gas gauge. I know I average between 200-220 miles per tank, depending on how my highway vs in-town driving I do. I just remember to reset my Odometer at every fill-up.

 

I had filled my tank and I only get about 130 until it says empty! Either I still have a lot of fuel left when it reads empty, or something else is wrong. Idrive real easy and at speed limit and everything else.

 

I'm glad I saw this thread. Went & looked at mine. I'm reading 202 miles & yet 1/2 tank of gas left. Better get gas on my next trip out!

Mine used to read accurately but a few months ago it started reading wrong. 1/2 tank on the gauge, yet the engine stumbled (low fuel) going around a corner!

 

could be a ground problem

 

How would I determine whether or not it is a gorund problem and how do I fix it?

 

If it was a ground problem, it would be causing errors across the full range of the float sweep. If its only reading inacturatly in a small range of the sweep, then my guess would be a contact problem between the points on the sweep and the points on the float arm.

If you pulled the sending unit out and worked the float manually and the gauge moved acurately, then it could just be a problem with the internal baffels in the tank keeping fuel around the float casuing it to read half full when its not.

 

Is there any way to fix that? I can also take the unit back out and recheck the float.

 

If theres a problem with the contacts, you might be able to adjust them. But most likely the fix would be a new sending unit.

 

Real simple. Just run a wire from the sending unit to the body of the car.
if the problem goes away I would think the problem was ground problem

 

I have a simliar problem on my 87 TA with a digital dash...thinking of replacing the sending unit, fuel pump( have to drop the tank anyways) and float. Do the sending unit lines run inside the car? I never saw then when I stripped the car down to the frame.

 

no, just the wiring runs inside the car, right behind the rear seat back.

 

If it IS a ground problem, where is the factory ground location for the unit? I could check that first, if it exists.

 

pretty sure that there is no ground wire, just body contact

 

pretty sure one of the 3 wires that go to the connecter behind the back seat is a ground, should be a grey or tan wire, a purple wire and a black wire. the grey or tan is the 12v for the pump, the purple is for the gauge and the black is the ground.

 

I'd check a wiring diagram to be sure. I just noticed it was a 92 so don't really know the wiring of every car in the world. if it is a three wire the acceptable voltage drop on the ground side is around 0.1 ish